Fly ash is the end product of combustion during the process of power generation in the coal-based thermal power plants. It is a proven resource material for many applications of construction industries and currently is being utilized in the manufacturing of Portland Cement, Bricks, Blocks & Tiles Manufacturing, Road Embankment Construction, and low-lying area development, etc. Among the many fly ash brick manufacturers in India, we are one of the leading fly ash bricks suppliers in Kolkata.

At present, 63% of the fly ash is being utilised and the target is for 100% utilisation of the fly ash. There is a need for education and awareness generation. Road contractors and construction engineers need to know the benefits of using fly ash cement bricks in construction. Measures need to be taken to reduce the cost of construction of roads using fly ash bricks by way of tax structure, subsidies, and transportation services.

What is the need of the hour?

• Research: Conduct more research on improving the quality of fly ash cement bricks, grading fly ash generated by different technologies and types of coal, and feasible blending ratios for the cement industry.
• Updating Standards: The BIS must update the blending standards, which have not been revised since 2000.
• Transparency: Improve transparency and reduce the costs of fly ash disposal by Coal power plants.
• Use renewable energy: Limit fly ash production through the greater deployment of renewable energy sources, using better coal and combustion techniques, etc, since cement-related industries alone will not be able to absorb all the fly ash generated in the future.
• Other needs: The key requirements for overcoming the barriers are greater regulatory oversight and price control, revision of cement blending standards, research in improving fly ash quality, reducing the cost of transportation, provisions for overcoming information asymmetries, and overall sensitisation of key decision-makers on the matter.

What are the issues which impede its full-scale utilization in India?

• Indian fly ash is primarily of the calcareous or class C variety, implying that it possesses not only pozzolanic but also hydraulic (self-cementing) properties. In contrast, European fly ash is of a silicious or class F variety, implying an absence of hydraulic properties.
• BIS revised the maximum and minimum blending standards. While the BIS is in line with the American standards on blended cement, the European and South African standards allow the blending of fly ash up to 55%.
• The pricing of fly ash is increasingly becoming a contentious issue that is hampering its gainful utilisation.
• Imperfections typical of quasi-markets, such as information asymmetry and high transaction costs, vested interests, technical and technological limitations, and the lack of regulatory oversight and political will, have impeded the flow of fly ash to its most value-adding use.

An insight into the quantitative analysis

For the purposes of quantitative analysis, 951 MT of cement production and 1,340 MT of coal in electricity generation by 2030 have been considered. On an average, the ash content in coal is 33% which implies that the annual fly ash generation by 2030 will be approximately 437 MT. If the current trends in utilisation of fly ash were to continue, overall the utilisation will tune-up to 310 MT by 2030. The cement’s share in utilisation, as a percentage of total fly ash generated, will increase from 25% to 35% by 2030.

While cement’s fly ash requirement will grow fourfold, to 151 MT in 2030, approximately 128 MT of fly ash will still remain under-utilized. This will require an additional 2,300 hectares of land and 1.3 billion cubic meters of water for ash ponds, exacerbating the existing problems concerning fly ash disposal. There is a need to prevent the ash from coming to the power plant by washing the coal at its place of origin. The government should also come out with a policy to encourage fly ash use in cement plants.

Harden Bricks Pvt Ltd. is among the leading fly ash brickworks in Kolkata, West Bengal. Our state-of-the-art fly ash bricks and fly ash cement manufacturing facility stretches over 3 acres of land and houses top-notch machinery that enables us to produce sturdy, long-lasting and eco-friendly bricks made of fly ash cement. To know more about our products, visit our website – www.hardenbricks.in